That's what I'm going to aim for so I can begin my teaching game by the end of august. And I can't think of any other army I want to play besides the Tyranids ^^
So i went out and bought my first purchases, one tyranid army book and a box of tyranid warriors. Two to do up as warriors and the the third to do as a prime. I know its probably not ideal, but at 600pts its just something to have a laugh. Plus you got to have a little love for the smaller gribblies.
I'm just not sure how to equip the warriors or prime. Any suggestions ?
If you have the Prime as your army leader (the warlord), then you'll want to have him with minimal upgrades to keep him cheap, so that you can spend more on the offensive part of your army.. If he's not the warlord (you need to get another HQ character), then you will want to give him close combat weapons that will be most useful against the armies you're most likely to face, and get him in so he can choppy-chop..
The warriors are an issue... you need at least 3 in the unit, so making 1 of the models into a Prime stops you from taking the Warriors at all... If you keep all the models as Warriors, then I'd recommend keeping them basic, with 1 upgraded with the bio-cannon.. Which bio-cannon to choose is, again, down to which armies you're likely to be playing against.. Barbed Strangler is more likely to hurt units of infantry (bigger blast means more models will get hit by the weapon, and more chances for your opponent to fail to save them), but the Venom Cannon will be more likely to hurt the opponent, and has a chance of hurting tanks (no 1-shot-kills but better than nothing)
Overall: I'd recommend using a friends army to get the basics of the game, and find out which armies tend to get used the most, so you know roughly what sort of stats you'll need to contend with